Vehicular ignition systems typically operate when electrical current flows through a primary winding of an ignition coil and this current flow induces energy to be stored in a magnetic field associated with the coil. The inductance of the coil, the amount of supply current applied to the coil, and the dwell time of the coil (i.e., the time set aside to build the current in the primary winding of the coil) are some factors that determine the amount of energy that can be stored in the magnetic field of the coil.
The stored energy of the coil is released when the primary winding current is suddenly turned off and the released energy flows from the magnetic field as a secondary current in a secondary winding of the ignition coil. Due to the high turns ratio typically used in coils and the rapid collapse of the magnetic field in the coil, a spark is generated across a spark plug that is attached to the secondary winding of the coil.
Different types of coil configurations have been used in previous vehicular ignition systems. To take one example, “pencil” coils are a special type of coil that have relatively long and narrow dimensions and have been used, for instance, in motorcycle ignition systems. In pencil coil arrangements, electronic coil drivers are typically used to drive the coils and a separate coil (and driver) are used to drive each cylinder of the engine. The coil drivers are themselves typically controlled by an electronic control unit (ECU), which controls the current dwell time for each coil.
In many demanding applications (e.g., drag racing), it is often desirable to retrofit the system to increase the energy in the system to thereby provide a stronger spark than is normally provided. In attempting to achieve this result, some users replaced their older coils with newer coils having lower inductances thereby increasing the current in the coil and, consequently, the amount of energy that could be stored in the magnetic field associated with the coil. However, these approaches required that existing coil drivers and existing ECUs be able to handle the larger currents associated with the newer coils. Unfortunately, existing coil drivers and ECUs often were damaged or destroyed by these increased currents making it impractical or impossible to increase spark energy in existing systems to the levels desired.
Because of these problems, it was difficult or impossible to retrofit existing systems to provide for increased spark energy or other enhanced spark characteristics while at the same time protecting and preserving existing system components. This resulted in user frustration with these previous systems and the general inability to achieve the increased performance levels desired by users.